Fuse wire is a wire of
low resistance and low melting point
low resistance and high melting point
high resistance and high melting point
high resistance and low melting point
At neutral temperature, the thermoelectric power is
infinite
zero
minimum
maximum
A 10 metre potentionmeter wire has a resistance of 20 Ω. It is connected in series with a battery of emf 2.5 volt and a resistance of 5 Ω. The potential gradient along wire in volt cm-1 is
0.002
0.02
0.2
0.0025
Kirchhoff's current law at a junction deals with conservation of
charge
energy
momentum
all of these
Potentiometer measures the potential difference more accurately than a voltmeter because
it has a wire of high resistance
it has a wire of low resistance
it does not draw current from external circuit
it draws a heavy current from external circuit
A 220 volt, 1000 watt bulb is connected across a 110 volt mains supply. The power consumed will be
750 watt
500 watt
250 watt
1000 watt
A steady current of 1.5 A flows through a copper voltameter for 10 min. If the electrochemical equivalent of copper is 30 ×10-5g C-1,the mass of copper deposited on the electrode will be :
0.40 g
0.50 g
0.67 g
0.27 g
Direct current is passed through a copper sulphate solution using platinum electrodes.The elements liberated at the electrodes are :
copper at anode and sulphur at cathode
sulphur at anode and copper at cathode
oxygen at anode and copper at cathode
copper at anode and oxygen at cathode
In electrolysis the mass deposited on an electrode is directly proportional to :
current
Square of current
concentration of solution
Inverse of current
The velocity of charge carriers of current(about 1A) in a metal under normal conditions is of the order of
a fraction of mm/s
velocity of light
several thousand m/s
a few hundred m/s
